Detector head position calibration and correction for SPECT imaging apparatus using virtual CT
AssigneeSiemens Medical Solutions USA, Inc.
InventorsSharon Xiaorong Wang, Joseph Fang
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Abstract
A multiple point source test phantom is used for calibration of detector positioning of a nuclear medical imaging apparatus. An absolute coordinate system for the detectors is aligned to an image reconstruction space coordinate system by fitting a Gaussian surface to a peak of a center point source of said test phantom, and using displacement parameters as obtained from the fitted Gaussian surface to calculate a displacement correction parameter, which is used to move a patient bed of the imaging apparatus such that the image reconstruction space is aligned with the absolute coordinate system.
Claims18
A method for calibrating a nuclear medical imaging apparatus having multiple detectors, comprising the steps of:
- determining at least one image center location on at least one of said multiple detectors;
- aligning a multiple isotope point source test phantom so that a center point source of said phantom lies within said center location;
- acquiring image data of said multiple point source test phantom with said detectors;
- fitting a Gaussian surface to a peak of acquired data of said center point source;
- using said fitted Gaussian surface to calculate a position of said center point source as an origin of a first coordinate system;
- and
- adjusting a position of said test phantom such that said calculated center point source position is aligned with said center location.
A method for calibrating a nuclear medical imaging apparatus having multiple detectors, comprising the steps of:
- determining at least one image center location on at least one of said multiple detectors;
- aligning a multiple isotope point source test phantom so that a center point source of said phantom lies within said center location;
- placing said detectors at first locations with respect to said test phantom;
- acquiring image data of said multiple point source test phantom with said detectors;
- fitting a Gaussian surface to a peak of acquired data of said center point source;
- using said fitted Gaussian surface to calculate a position of said center point source as an origin of a first coordinate system;
- adjusting a position of said test phantom such that said calculated center point source position is aligned with said center location;
- placing said detectors at second locations with respect to said test phantom;
- acquiring image data of said multiple point source test phantom with said detectors at said second locations;
- fitting a Gaussian surface to a peak of acquired data of said center point source at said second locations;
- using said fitted Gaussian surface at said second locations to calculate a position of said center point source as an origin of said first coordinate system;
- and
- adjusting a further position of said test phantom such that said calculated center point source position is aligned with said center location position.
Dependencies are inferred from the claim text.